Sentinel lymph node biopsy is associated with improved survival compared to level I & II axillary lymph node dissection in node negative breast cancer patients

Objective

The few long-term follow-up data for sentinel lymph node (SLN) negative breast cancer patients demonstrate a 5-year disease-free survival of 96–98%. It remains to be elucidated whether the more accurate SLN staging defines a more selective node negative patient group and whether this is associated with better overall and disease-free survival compared with level I & II axillary lymph node dissection (ALND).

Methods

Three-hundred and fifty-five consecutive node negative patients with early stage breast cancer (pT1 and pT2 ≤ 3 cm, pN0/pN_SN0) were assessed from our prospective database. Patients underwent either ALND (n = 178) in 1990–1997 or SLN biopsy (n = 177) in 1998–2004. All SLN were examined by step sectioning, stained with H&E and immunohistochemistry. Lymph nodes from ALND specimens were examined by standard H&E only. Neither immunohistochemistry nor step sections were performed in the analysis of ALND specimen.

Results

The median follow-up was 49 months in the SLN and 133 months in the ALND group. Patients in the SLN group had a significantly better disease-free (p = 0.008) and overall survival (p = 0.034). After adjusting for other prognostic factors in Cox proportional hazard regression analysis, SLN procedure was an independent predictor for improved disease-free (HR: 0.28, 95% CI: 0.10–0.73, p = 0.009) and overall survival (HR: 0.34, 95% CI: 0.14–0.84, p = 0.019).

Conclusions

This is the first prospective analysis providing evidence that early stage breast cancer patients with a negative SLN have an improved disease-free and overall survival compared with node negative ALND patients. This is most likely due to a more accurate axillary staging in the SLN group.